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71.
A Novel Graphene Oxide Wrapped Na2Fe2(SO4)3/C Cathode Composite for Long Life and High Energy Density Sodium‐Ion Batteries 下载免费PDF全文
Mingzhe Chen David Cortie Zhe Hu Huile Jin Shun Wang Qinfen Gu Weibo Hua Enhui Wang Weihong Lai Lingna Chen Shu‐Lei Chou Xiao‐Lin Wang Shi‐Xue Dou 《Liver Transplantation》2018,8(27)
The cathode materials in the Na‐ion battery system are always the key issue obstructing wider application because of their relatively low specific capacity and low energy density. A graphene oxide (GO) wrapped composite, Na2Fe2(SO4)3@C@GO, is fabricated via a simple freeze‐drying method. The as‐prepared material can deliver a 3.8 V platform with discharge capacity of 107.9 mAh g?1 at 0.1 C (1 C = 120 mA g?1) as well as offering capacity retention above 90% at a discharge rate of 0.2 C after 300 cycles. The well‐constructed carbon network provides fast electron transfer rates, and thus, higher power density also can be achieved (75.1 mAh g?1 at 10 C). The interface contribution of GO and Na2Fe2(SO4)3 is recognized and studied via density function theory calculation. The Na storage mechanism is also investigated through in situ synchrotron X‐ray diffraction, and pseudocapacitance contributions are also demonstrated. The diffusion coefficient of Na+ ions is around 10?12–10?10.8 cm2 s?1 during cycling. The higher working voltage of this composite is mainly ascribed to the larger electronegativity of the element S. The research indicates that this well‐constructed composite would be a competitive candidate as a cathode material for Na‐ion batteries. 相似文献
72.
73.
Renal cell carcinoma (RCC) is one of the most common malignancies in the urinary system. Due to the lack of early symptoms, diagnosis of RCC usually occurs at late stages or after cancer metastasis leading to poor prognosis. Therefore, it is crucial to study early molecular mechanisms and biomarkers. Previous studies have suggested that microRNAs are involved in RCC initiation and development, making them a good candidate for early diagnosis and therapy. MiR146b-5P plays important roles in the progression of multiple cancers including thyroid cancer, pancreatic cancer, cervical cancer. However, it is not clear whether and how miR146b-5P is involved in RCC. In this study, we aimed to investigate the function of miR146b-5P in RCC. We examined the expression levels of miR146b-5p in renal cancer tissue and cell lines. We also explored the effects of blocking miR146b-5p in renal tumor growth and inflammatory signaling. Finally, we determined if miR146b-5p regulates tumorigenesis through TRAF6. We found that miR146b-5p levels were significantly increased in renal cancer tissue and renal cancer cells. Blocking miR146b-5p suppressed renal tumor growth and enhanced inflammatory response through increased TRAF6 expression. These effects were eliminated in TRAF6 knockout mice. Our results suggest that enhanced miR146b-5p expression may be a biomarker for RCC and modulating miR146b-5p and TRAF6 levels represent a potential therapeutic strategy for RCC. 相似文献
74.
本文对236例(472侧)中国成人颅骨的脑膜中动脉眶支沟、脑膜中动脉眶支孔和眶外侧沟进行了观察。主要结果如下:脑膜中动脉眶支孔的出现率为55.9%;眶外侧沟的出现率为17.6%,其中双侧出现的有24例,占10.2%。 相似文献
75.
股骨头负重区松质骨的压缩力学特性 总被引:6,自引:0,他引:6
本文对19具新鲜青年(30左右)尸体股骨负重区的松质骨进行了压缩测试,测算并提供了一组松质骨弹性模量,极限应力,应变,屈服载荷及能量吸收值。试验表明松质骨力学性能主要缓解外力冲击加压。 相似文献
76.
摘要:【目的】本研究通过百日咳杆菌黏附素(PRN)基因的分段克隆表达及其在BALB/c小鼠的主动和被动免疫保护试验筛选PRN中的保护性抗原肽。【方法和结果】利用大肠杆菌进行PRN的完整蛋白、N端和C端多肽及其RI和RII区域多肽(双拷贝)的表达,命名为GST-PRN、GST-PN、GST-PC、GST-2PRI和GST-2PRII。Western blot检测证实5种表达产物均具有良好的反应原性。在主动免疫保护试验中,5种表达产物均能诱导小鼠产生较高的PRN抗体水平;当使用3 LD50的支气管败血波氏杆菌 相似文献
77.
OsTDL1A binds to the LRR domain of rice receptor kinase MSP1, and is required to limit sporocyte numbers 总被引:1,自引:0,他引:1
Zhao X de Palma J Oane R Gamuyao R Luo M Chaudhury A Hervé P Xue Q Bennett J 《The Plant journal : for cell and molecular biology》2008,54(3):375-387
Hybrids lose heterotic yield advantage when multiplied sexually via meiosis. A potential alternative breeding system for hybrids is apospory, where female gametes develop without meiosis. Common among grasses, apospory begins in the nucellus, where aposporous initials (AIs) appear near the sexual megaspore mother cell (MeMC). The cellular origin of AIs is obscure, but one possibility, suggested by the mac1 and msp1 mutants of maize and rice, is that AIs are apomeiotic derivatives of the additional MeMCs that appear when genetic control over sporocyte numbers is relaxed. MULTIPLE SPOROCYTES1 (MSP1) encodes a leucine-rich-repeat receptor kinase, which is orthologous to EXS/EMS1 in Arabidopsis. Like mac1 and msp1, exs/ems1 mutants produce extra sporocytes in the anther instead of a tapetum, causing male sterility. This phenotype is copied in mutants of TAPETUM DETERMINANT1 (TPD1), which encodes a small protein hypothesized to be an extracellular ligand of EXS/EMS1. Here we show that rice contains two TPD1-like genes, OsTDL1A and OsTDL1B. Both are co-expressed with MSP1 in anthers during meiosis, but only OsTDL1A and MSP1 are co-expressed in the ovule. OsTDL1A binds to the leucine-rich-repeat domain of MSP1 in yeast two-hybrid assays and bimolecular fluorescence complementation in onion cells; OsTDL1B lacks this capacity. When driven by the maize Ubiquitin1 promoter, RNA interference against OsTDL1A phenocopies msp1 in the ovule but not in the anther. Thus, RNAi produces multiple MeMCs without causing male sterility. We conclude that OsTDL1A binds MSP1 in order to limit sporocyte numbers. OsTDL1A-RNAi lines may be suitable starting points for achieving synthetic apospory in rice. 相似文献
78.
Yang X Yu RH Calmettes C Moraes TF Schryvers AB 《The Journal of biological chemistry》2011,286(52):45165-45173
Gram-negative bacterial pathogens belonging to the Pasteurellaceae, Moraxellaceae, and Neisseriaceae families rely on an iron acquisition system that acquires iron directly from host transferrin (Tf). The process is mediated by a surface receptor composed of transferrin-binding proteins A and B (TbpA and TbpB). TbpA is an integral outer membrane protein that functions as a gated channel for the passage of iron into the periplasm. TbpB is a surface-exposed lipoprotein that facilitates the iron uptake process. In this study, we demonstrate that the region encompassing amino acids 7-40 of Actinobacillus pleuropneumoniae TbpB is required for forming a complex with TbpA and that the formation of the complex requires the presence of porcine Tf. These results are consistent with a model in which TbpB is responsible for the initial capture of iron-loaded Tf and subsequently interacts with TbpA through the anchor peptide. We propose that TonB binding to TbpA initiates the formation of the TbpB-TbpA complex and transfer of Tf to TbpA. 相似文献
79.
Sun W Xing B Sun Y Du X Lu M Hao C Lu Z Mi W Wu S Wei H Gao X Zhu Y Jiang Y Qian X He F 《Molecular & cellular proteomics : MCP》2007,6(10):1798-1808
Hepatocellular carcinoma (HCC) is a highly malignant tumor, and chronic infection with hepatitis B virus is one of its major risk factors. To identify the proteins involved in HCC carcinogenesis, we used two-dimensional fluorescence DIGE to study the differentially expressed proteins in tumor and adjacent nontumor tissue samples. Samples from 12 hepatitis B virus-associated HCC patients were analyzed. A total of 61 spots were significantly up-regulated (ratio >/= 2, p = 0.01) in tumor samples, whereas 158 spots were down-regulated (ratio = -2, p = 0.01). Seventy-one gene products were identified among these spots. Members of the heat shock protein 70 and 90 families were simultaneously up-regulated, whereas metabolism-associated proteins were decreased in HCC samples. The down-regulation of mitochondrial and peroxisomal proteins in these results suggested loss of special organelle functions during HCC carcinogenesis. Four metabolic enzymes involved in the methylation cycle in the liver were down-regulated in HCC tissues, indicating S-adenosylmethionine deficiency in HCC. Two gene products, glyceraldehyde-3-phosphate dehydrogenase and formimidoyltransferase-cyclodeaminase, were identified from inversely altered spots, suggesting that different isoforms or post-translational modifications of these two proteins might play different roles in HCC. For the first time, the overexpression of Hcp70/Hsp90-organizing protein and heterogeneous nuclear ribonucleoproteins C1/C2 in HCC tissues was confirmed by Western blot and then by immunohistochemistry staining in 70 HCC samples, suggesting their potential as protein tumor markers. In summary, we profiled proteome alterations in HCC tissues, and these results may provide useful insights for understanding the mechanism involved in the process of HCC carcinogenesis. 相似文献
80.
祁连山地区植被特征及其分布规律 总被引:22,自引:0,他引:22
分析和讨论了祁连山地区主要植被类型及其分布特征。祁连山地区随着青藏高原的强烈隆升表现为整体抬升,植被具有明显的生态地理边缘效应特征和高原地带性规律。该区植被虽然受到四周的较大影响,但各类高寒植被占有绝对优势,表现出与青藏高原植被整体明显的相似性和广泛的一致性。另一方面,本区植被也有其特殊性及与高原面存在一些差异。因此,建议把祁连山地区做为青藏高原植被区的次一级独立单元 相似文献